Any methods of finding TDC without timing marks?

[ericarmstrong]

I have reason to believe my damper timing mark may have shifted. Anyone have a method for accurately testing this?

[ammachine390]

Couldn't you spin the engine until the distributor rotor gets to the number 1 spark plug tower on the cap. It wouldn't be exactly TDC but it would be close, just a little BTDC.

[ericarmstrong]

Only issue there is that I static timed the distributor according to the damper mark.

[ericarmstrong]

The screwdriver sounds like a plan to me. I may try the old  thumb over hole 1 method instead of pulling the valve cover to ensure I'm not 180 out.

[AMCKen]

...and if you have the screwdriver in just enough that you can't/won't turn the engine anymore, mark the spot on the damper. Then turn the opposite way until it stops again and mark it. TDC will be halfway between the marks.

[ammachine390]

if the car still runs, you can still use the distributor rotor position to make sure you are not off 180 degrees

[ericarmstrong]

if the car still runs, you can still use the distributor rotor position to make sure you are not off 180 degrees

The car runs like a champ, and that's a good idea.

[doneagle]

you pull spark plug out of #1 hole. pull off valve cover. drop a long screwdriver into the plug hole. crank engine around till the screwdriver stops going up. now, you have to make sure that BOTH intake and exhaust valves are closed. if they are not both fully up, your 180* off. that will get you about as close as you can get without pulling off and installing a new damper.

              HI    if you don't want to take the valve cover do what Casper said .When you get the piston up .look at
              the taming mark and see if its right on or 180 out....the thumb will get you close .....Don